Ejercicio excéntrico de baja intensidad y daño muscular en mujeres jóvenes. Un estudio piloto. (Low intensity eccentric exercise and muscle damage in young women. A pilot study)

Abstract

Knee flexor muscle activity is very important to reduce the loads on the knee joint that could lead to an injury. The aim of the present study was to assess the effects of a low volume, low intensity eccentric exercise bout of the knee flexor muscles on the muscle function of the knee joint, and on the ground reaction forces during landings from an elevated surface. Fifteen young, active women volunteered for the study. They performed two low volume, low intensity eccentric exercise bouts with the knee flexors, separated by one week. Before and an hour later than both exercise sessions, we measured ground reaction forces during landings from elevated surfaces, and the moment-angle relationship from knee flexors and extensors. We also measured delayed muscle soreness. There were no significant changes in the peak torque of knee flexors and extensors (from -4.8 to 2.1%), nor in the angle of peak torque (from 3.4 to 5.4%). We also did not find an stable pattern in the changes in the ground reaction forces during landings. However, we did find significant differences in the delayed muscle soreness, with a significant decrease after the second eccentric bout, compared with the first one. The present results suggest that low volume, low intensity eccentric exercise of the knee flexor muscles can lead to positive adaptations on indirect markers of muscle damage, with a protecting effect against muscle damage in subsequent bouts of eccentric exercise.